Low Angle LightsOpposing LEDs with shallow incidence angles provide low angle illumination.
CA-DLR

Surface/edge chip

Typically, surface and edge defects are hard to detect with standard lighting as there is little contrast change. The low angle light highlights the physical change in the target making detection possible.

Low angle light illumination techniques

Low angle lighting provides direct light at a shallow angle onto the target. Typically inspection of the edge of a target or physical flaws on the surface are hard to detect with standard direct lighting. As the direction of the light is almost parallel to the surface any change in surface height deflects the normal path of light to the camera, subsequently highlighting the change.